Screw and nut driving machine



June 29,1926. 7 1,590,670

- s. K. BROWN scREw AND 1m muvme momma ori Fil ed March 5, 1921 z sneets-sheet 1 lNVENT0R.

ATTORNEYs,

June 29 1926. 1,590,670 s. K. BROWN SCREW AND NUT DRIVING- MACIIINE.v

origina Filed March 5. 1921 2 Sheets-Sheet 2 3 Z 22 I w: 1' [5 0 zw/pzfium A TTORNEY-S' 3 Patented June 29, 1926.

UNITED STATES PATENT ome SPENCER K. BROWN, 01? SYRACUSE, NEW YORK, ASSIGNOR TO THE BLACK-& DECKER MANUFACTURING COMPANY, LAN D.

OF TOWTSO N, MARYLAND, AOORIPOBATION OF MARY- SCBEW AND NUT DRIVING MACHINE.

Application filed March}, 1921; Serial No. 449,305. Renewed April 29, 1928.

This invention relates to screw and nut driving machines of the type described in my Patent N 0. 1,320,375 issued November l, 1919, and has for its object a' particularly 6 simple and'eflicient means for efiecting the engagement and disengagement of the wrench head from the driver therefor, and

a particularly simple and efficient means for increasing the driving force to be applied to to the screw or nut when it is desired to unscrew the screw or nut.

The invention consists in the novel fea- 'tures and in the combinations and construc tions hereinafter set forth and claimed. to In describing this invention, reference is like characters designate corresponding parts in all'the views.

Figure 1 is a. fragmentary elevation of this machine, the motor beingomitted.

Figure 2is a sectional view looking to the left taken on line 2-2, Fig.1.

Figures 3 and 4 are respectively, an en .larg'ed end elevation and sectional view of the wrench head.

Figure 5 is a detail view of the cams for additionally tensioning the friction clutch spring when the machine is operated to unscrew the screws or nuts. 3D Figures 6 and 7 are face views of the cams or collars shown in Fig. 5.

Figure 8 is an enlar ed fragmentary view of the clutch teeth of t e driving'and driven sections of the driven element.

This screw drivin machine comprises generall rotatable driving and driven elemerits, t e driven element including two sections a friction clutch connecting the driving element and the driving section of the driven element, the sections of the driven element havin clutch teeth on their opposing ends'and eing normally spaced apart, the driving section of the driven element being shiftable axially to engage and disengage the clutch teeth, and said clutch teeth being shaped to initially engage and slip ast each other when the driving section is first shifted axially and quickly separate the sections when the force applied tothe driving section to move it axially, is discon tinned.

1 designates the main frameof'the machine which may be of any suitable form, size and construction to carry a motor which may be an electric motor or a compressed air motorwhich actuates a suitable driving gear 2. J V 3 is a head or frame carried by the main frame 1 and carrying the screw and nut driving mechanism forming the subject mat-.

ter of this invention, this head 3 being suitably carried by the main frame. The main frame and head are here shown as formed with bearings 4 which slidaloly receive guide rods fixed to a suitable support as a carriage along which rods the frame slides to position the nut driving mechanism relatively to the work. This head is usually carried in vertical position but may be arranged in any convenient position to operate on the work had to the accompanying drawings in which end of the shaft and journaled in bearings 9 in the lower end of the head 3.

The driving element 5 has a bearing 10 on the shaft 6 of the driven element and coacts at its lower end with a thrust or journal bearing 11 on the frame head.

The driving element 5 is also fixed by keys 9 to the hearing or sleeve 9 extendmg' through the lower end of the frame head 3 and journaled therein by the bearings 11 which are common to the driving element 5 and sleeve 9. In fact, this sleeve is practically a unit with the driving element. Ad'- ditional bearings 12 are interposed betweenv the lower end of the bearing (2 sleeve 9 and the frame head 3. The driving section or shaft of the driven element extends through the driving element 5 into the sleeve or bearing 9 and has a head 15 mounted on the lower end thereof which is keyed thereto at 16 and held from displacement by a screw -18. This head fits into a toolholder or sleeve 19 having a contracted lower end 20 in which the driven section 7 or tool of the driven element is located. The sleeve 19 is journaled in a suitable hearing or bushing 21 located in the lower end of the frame head and-ar ranged between the sleeve 19 and the hearing or sleeve 9. The driven section 7 is here shown as a wrench head having an enlargeis sufiicient to cause the teet face of the contracted part of the sleeve separate when the driven section 7 is stopped from rotation as when the nut or ,screw is turned to its fullest extent and the driving section continues to be rotated by the driving element. v

The wrench head or driyen section 7 is formed with a polygonal 'or hexagonal socket, and with means at the entrance of the socket for guiding the head of a screw or nut into the socket, this means being here shown as a countersunk annular recess 26, the socket opening through the bottom of the recess at the angles of its sides. This recess is also applicable to hand operated socket wrenches.

.When the, machine is in operation, the wrench head or section 7 is usualiy rotating by .its own momentum when the sections 6, 7 are disengaged, thatfis, when the clutch teeth 24, 25 are se arated When the section 6 is first move downwardly, the sleeve '19 also moves therewith, thus moving the wrench head 7 downwardlyonto a nut and this wrench head is rotating by the momen-' tum of the previous operation or by the cuff;

. ing or knockingaction of the clutchteeth 24 on the ends'of the teeth 25. The recess 27 encloses the top of the nut and holds the nut centered, untll it slips into the socket 26. The machine is then shiftedwo bring the nut over the screw to receive it and the section 6 moved downwardly to full engage the clutch faces 24, 25 whereupon the nut is turned on the screw. Q y

The sleeve 19 moves downward when the shaft section 6 i's'moved downward,,for the reason that the clutch teeth 24. hitting on the ends 10f the clutch teeth 25 force the wrench head 7 downwardly rather. than come into interlocking engagement with the teeth 25, and such downward forcing of the wrench head 7 carries the Sleeve 19 downwardly until movement is stopped by the j wrench head'engaging the 'nut. Also the friction between the head 15 and the sleeve s'to, carry the sleeve 19 up and down If the. wrench head 7 is not rotating, or if the nut has been started by hand on the screw, when the clutch teeth 24 commence or initially engage the clutch teeth 25, owing to:

to cam apart or b the rapid rotation of the shaft fi, the clutch teeth 24 merely cuff and slip past the clutch teeth 25, rotating the wrench head 7 on the nut in the recess 27 sufficiently to at some point, bring the sides of the socket in alinement with the sides of the nut so that the nut slips from the recess into the socket. This cuifin operation is possible owing to the taper o the clutch teeth 24, 25.

Owing to the recess 27 it is practical to feed the nuts from a magazine, as it is not necessary to fit the nuts into the socket 26 of the wrench head by hand or to place them hand on the screws. It will 'be understood that the frame of the machine is suitably mounted to permit it to be swung horizontally and vertically to suit the convenience of the operator. This mounting of the frame forms no part of this invention.

The driving element 5 and the section 6 of the driven element are connected together by a friction disk clutch as in m patent referred to the clutch consisting o interleaved disks 28 and 29 keyed respectively. to the driving element 5 and shaft 6, these disks be-- ing pressed together by a spring 30 coiled about the shaft 6 within the element 5 and thrusting) at one 'end against an adjustable spring a utment 31 and at. its other end towardhe disks to press them against the upper end of the member or sleeve 9.

The spring is initially tensioned to exert sufficient pressure on the disks to drive the nut to turn the same to its final position and then to slip when the nut becomes stationary in its final position in case the operator continues to press the shaft 6 downwardly. The abutment 31 is adjustable by means of a sleeve 32 encircling the bearing or bushing 10 and threading 1n the neck or upper portion 33 of the'driving element 5.

Obviously, it will require slightly more friction to unscrew a nut than to screw it in position and in order to meet this condition, If have provided a particularly simple and efiicient means for automatically increasing the tensioning of the spring 30 when the machine is used to unscrew nuts or screws.

As here shown, this means comprises cams, one o erable'by the driving element 5 and the ot er forimngban abutment for one end of: the spring 30', the cams having inclined faces which act to move the spring abutment cam axially andhence compress the spring when the driving element is rotated in a reverse direction. As here illustrated, these cams are collars: 34, 35, the collar 34 bein rotatable with the driving element 5 at e disks 28 associatedwith the driving element and the collar 35 bein slidable on the shaft 6 and'forming an a utment for the lower'end of the sprm 30. The collars are provided with comple ental inclined or cam surfaces 36, 37 on their opposing faces so that when the driving element 5 is rotated gear 38 on the driving element 5 and when an air motor is used the motor itself is reversedand when the electric motor is used suitable reverse gear is formed, these fea' tures forming no part of this invention.

The shaft 6 is fed downwardly by said lever 39 pivoted at 40 to the frame and connected by links 41, 42 to a cbllar the upper end of the shaft 6.

43 fixed to 37 of the spring abutment collar 35 and shift the collar 35 upwardly to additionally ten; sion the clutch spring 30 sufliciently to hold the disks 28, 29 engaged without slipping so that the wrench head 7 is turned to unscrew the nut.

This machine is equally applicable to driving cap screws or screws with slotted heads.

What I claim is:

1. In a screw and nut driving machine, the combination of a rotating driving element, a rotating driven element, a friction clutch connecting said elements, a spring for normally engaging the clutch during rotation of the driving element forwardly, means for actuating the driving element in either direction, and means for automaticah 1y additionally tensioning the spring during movement of the driving element in, the reverse direction, substantially as and for the v purpose described.

In operation, the workman first swings 2. In a screw and nut driving machine,

- the frame 1 to position the wrench head 7 the combination of a rotating driving ele-' over the nut and the lever 39 is pulled for-.

7 axially until the annular recess 27 encloses tion of the me'ntya rotating driven element, a friction wardly or to the right Fig. 1. This moveclutch connecting said elements, a spring for 0 ment first feeds the shaft 6 and wrench head normally enga ng the clutch during rota- I riving element forwardly, the top of the nut when additional downmeans for actuating the driving element in ward movement shifts theshaft'6 downwardeither direction, an means for automatically relatively to the wrench head causing the ly additionally tensloning the/spring during clutch teeth 24 at the lower end thereof to movement of the driving element in the refirst cuff and sli past the clutchteeth 25 on verse d1rect1on, said means comprising an the wrench hea 7, thus turning the wrench axlally movable spring abutment at one end head so that the walls of the socket 26 aline 'of the spring, and cam means rotatable with with the sides of the nut and the nut slips he d vmg member and arranged to shift into the socket 26 as the shaft 6 movesdowntheabutmen't axially to tension the spring wardly to ositively engage the clutch teeth during movement of the driving member in 24,25. Al the foregoi tion t ke reverse dlrection, substantially as and for place without the exercise of any skill by he purpose Set forth; the workman who merely win the m 3. In a screw and .nut drivin machine, chine to position the wrench head and pulls he Ombma iOH of a rotating riving eledown naturallyon th h dl 39, Wh th ment, a rotating drlven element, a friction nut has been screwed down the friction disks clutch connechng id e em nts, a spring 28,29 slip. The operator then releases the. for normally engaging the clutch during handle39 and the shaft'6 moves automaticah l'otatloll 0f BdliViDg-element forwardly, 110 ly upwardly owing to the taper of the clutchmeans Q j g' h riving element In teeth 24, 25. The operation isthen repeated. i h r d1rect1on, and m f r ma in n inu usly opera-ted .it requires cally additionally tensioning the sprin durabout .6 of a second to drive each nut g movementpf h d ivi g-element 1n the In unscrewing d removing nuts, th reverse d1rect1on, said means compr sing 115 erator moves th hi t place th collars rotatable respectively with the drivwrench head 7 on the nut and proceeds the g and drlven elem f the 00113! on the same as before except'that the direction of dllven e1ement be1ng 1n abutment-fol one rotation of the motor or shaft 6 is'reversed, end of the sprlng and the collam havingfl/ the direction of rotation of the shaft 6 bems n ir opp sing faces arr mged 00 ing reversed due to the direction of rotation separate the collars when the driving element is turned in reverse direction and permit the collars to come toward each other and the spring to expand when the driving member is rotating in a forward direction,

fsiullstantially as and for the purpose speci- 4. In a screw and nut driving machine,

the combination of a driving element, a driven element arranged axially of the driving element, a friction clutch connecting sald elements, a collar encircling the driven element and rotatable with a friction mem ber of the driving element, a collar slidable axially of the driven element, the collars having cam faces on their opposing sides for sprea ing the collars apart during relative rotation of the driving element relatively to the driven element 'in one direction, and a compression spring abutting against the axially shiftable collar tending to pressv the collars and the friction members of the clutch together,substantially as and for the purpose setforth.

5. In ascrew and nutdriving machine, the combination of a driving element, a driven element extending coaxially of the driving element, a friction clutch interposed between the driving and driven elements, a

2 collar encircling the driven element and be;

element, a collar mounted roon their opposing faces whereby upon relative rotation upon the driving and drivenelements in one direction, the collar associated with the driven element is moved axially, a spring encircling the driven;element and pressing at one end against the collar on the driven element and at its other end against the driving'element, substantial ly as and for the purpose described.

In testimony whereof, 1 have hereunto signed my name at Syracuse, in the county of Ononda a, and State of New York, this 16th day 0 December, 1920.

SPENCER'K. BROWN. 

